1. Field of the Invention
The present invention relates to a magnetic resonance imaging apparatus, a setting supporting apparatus, and a setting supporting method capable of providing information for supporting placement of a patient on a bed top board and placement of an RF coil for the patient in magnetic resonance imaging.
2. Description of the Related Art
The magnetic resonance imaging is an imaging method of magnetically exciting nuclear spins in a subject who is put in a magnetostatic field by an RF signal of the Larmor frequency, obtaining an MR signal generated in association with the excitation, and reconstructing an MRI image and an MRA image (hereinbelow, called MP images).
In the magnetic resonance imaging, an RF coil having a shape adapted to a region to be imaged (imaging region) is selected and disposed on the surface of the subject or near the subject. A subject is placed on the bed top board, and the RF coil is placed on the surface of the subject. After that, the imaging region is adjusted to a laser beam projection position of a laser projector disposed in the front face of a gantry of a magnetic resonance imaging apparatus. The imaging region is then sent to a magnetic field center (isocenter) in the center of the gantry by a bed horizontal moving mechanism of the magnetic resonance imaging apparatus.
If the RF coil is not placed in the optimum positional relation with the imaging region, a high-quality image cannot be obtained. Generally, placement of a subject and an RF coil in conventional magnetic resonance imaging is executed according to a method of placing an RF coil and the like described in an instruction manual or relying on the experience of the operator himself/herself.
However, the optimum coil placement position slightly varies depending on the body shapes of subjects and lesions to be imaged. Therefore, whether a subject or an RF coil can be placed properly or not (that is, whether an image of an imaging region can be acquired with high quality or not) depends on the coil setting skill of the operator. In some cases, the quality of a diagnosis image varies among operators.
For example, in the case of performing imaging to check the course of a treatment, it is preferable to place a coil in the same position as that in the previous time. It is, however, difficult even for the same operator to reproduce the placement of a subject and a coil of last time with high precision. It is more difficult for an operator to reproduce the placement of a subject and a coil performed by another operator.
Further, at the time of adjusting an imaging region to a laser projector, generally, the imaging region is moved by using a slow configuration of a bed horizontal moving mechanism to a magnetic field center position. During the bed horizontal movement, the operator has to visually observe the positions of a subject and an RF coil. Consequently, an artificial load is heavy.